The present invention relates generally to surgical micro-cutting instruments. More particularly, it relates to a surgical micro-resecting instrument integrating both mechanical and electrical current cutting as well as facilitating continuous aspiration.
Surgical cutting instruments in which an elongated inner member is rotated within an elongated outer tubular member have become well accepted in surgical procedures where access to the surgical site is gained via a narrow portal or passage. Typically, the outer tubular member includes a distal section terminating at a closed distal end and defining a cutting port or window proximal the distal end, and the inner member includes a distal portion forming a cutting tip for cutting bodily tissue at the cutting window. Proximal ends of the inner and outer members are commonly secured to hubs that, in turn, are attached to a power handpiece for rotating and/or oscillating the inner member relative to the outer tubular member. The cutting tip of the inner member can have various configurations specific to the surgical procedure in question (e.g., cutting, resecting, abrading, shaving, etc.), with the cutting window being suitably configured to cooperate with the particular configuration of the cutting tip. Often, the inner member is tubular so that the loose tissue resulting from a cutting, resecting, or abrading procedure can be aspirated through the hollow lumen of the inner tubular member via the cutting window. With specific reference to ENT applications, such as ethmoidectomy, sinus surgery, adenoidectomy, laryngeal surgery, etc., extremely sharp, micro-resecting blades or cutting tips are typically employed to effectuate the procedure.
The above-described surgical instruments rely upon a mechanical cutting action to resect, cut, shave, abrade, etc., the tissue in question. With respect to ENT procedures, mechanical-type, micro-resecting instruments are highly viable and present distinct advantages over other available devices. For example, CO2 lasers are available. However, laser-based systems are expensive and present the distinct risk of thermal trauma or burns.
Efforts have been made to improve upon the design of surgical-resecting instruments. For example, the blade or cutting tip configuration can be optimized for certain applications. Further, so as to facilitate access to certain bodily areas, the surgical cutting instrument has been modified from a generally straight form to one having a fixed- or variable-angle design.
Often times, during an ENT micro-resecting procedure, it is necessary to coagulate or otherwise stem bleeding at the target site to provide hemostasis. The accepted technique for effectuating hemostasis is to remove the micro-resecting instrument and deploy a separate coagulation device. While necessary, this technique is highly time consuming. To overcome this problem, efforts have been made to develop a surgical micro-resecting instrument providing an integrated electrocautery feature, such as that described in U.S. patent application Ser. No. 09/961,543, filed Sep. 24, 2001, the teachings of which are incorporated herein by reference. While adequately eliminating the need for a separate coagulation device, these and other techniques may give rise to other concerns. For example, the exposed, energized surface area of the instrument is often times relatively large, potentially leading to less than optimal energy distribution at the target site. Additionally, and similar to other micro-resecting instruments, it is difficult, if not impossible, to adequately aspirate blood and other bodily tissue into and through the instrument, especially when the cutting window is “closed” by the cutting tip.
Surgical micro-resecting blade instruments continue to be extremely useful. Recent improvements to incorporate an electrocautery feature into the instrument appear promising. However, a need exists for a surgical micro-resecting instrument incorporating an optimized electrocautery feature that facilitates continuous aspiration where desired.